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In Earth-616 some are still alive.

For clarification, Thanos is an Eternal of Titan.

Titan
Sui-San - Descendant of Uranos's followers on Titan. She was the only survivor of the war on the surface of Titan. She was found by A'lars, who with her, founded the new Eternals of Titan. Sui-San's children included Eros and Thanos. She was slain by Thanos during his attack on Titan, when he dissected her with a medical kit, hoping to learn why he was different from other children.
Mentor (A'lars) - Assumed as head of the Eternals of Titan. Son of Kronos, brother of Zuras, father of Eros and Thanos.
Thanos - Son of Mentor and Sui-San, brother of Eros. Is a Mutant Eternal, with purple skin and a ridged chin, plus more power than a typical Eternal of Titan, including energy blasts, psionic abilities, and teleportation. Raised the child Gamora, and trained her to become the ultimate assassin.
Starfox (Eros) - Titanian Eternal, child of Mentor and Sui-San and younger brother of Thanos. Became known on Earth as a hero. Former member of the Avengers, under the alias "Starfox". Has the power to control the emotions of others.
Demeityr- List of Eternals - Wikipedia

Most of these are alive.

In Mcu we don't know of any.

The Eternals are never seen in any of the movies.

There are rumors the as-yet-untitled Avengers 4 could actually feature Kronos and the Eternals. There's a sense in which that's hardly a surprisel; Marvel is known to be working on an Eternals movie as part of the post-Phase 3 MCU, and Jim Starlin recently hinted that Avengers 4 would introduce another one of his comic book characters.- How The Eternals Can Fit Into Avengers 4 - ScreenRant

They are hinted at though.

Avengers: Infinity War set up the Eternals in a number of subtle ways. When the Red Skull speaks to Thanos, he identifies him as the son of A'lars. That's a crucial detail, given that in the comics A'lars (sometimes known as Mentor) isn't just Thanos's father. He's also the founder of the Eternals. There's a brief scene where Thanos uses the Reality Stone to show Titan in its glory days, and the beings there are clearly humanoid - and, just as in the comics, don't share Thanos's distinctive physical appearance. While Thanos is an Eternal in the comics, he possesses the Deviant gene, making him appear significantly different than the rest of his race. It seems that's true in the MCU as well. VFX supervisor Matt Aitken told Screen Rant that this was originally a longer sequence, and would have involved a clearer glimpse of Titan's inhabitants.- How The Eternals Can Fit Into Avengers 4 - ScreenRant

It's worth noting that the above is 616 canon, not Earth-199999 (MCU). There is, as yet, no definitive answer within the MCU continuity (happy to be corrected if one of the prelude comics addresses this?)
– John Smith OptionalJan 27 at 18:14

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So that means the appearance of Thanos is a particular case?
– Kushal BhuyanJan 28 at 3:58